In electrophotography, photoconductive materials including selenium are generally used as photoreceptors, and an electric latent image is formed on the photoreceptor by various methods. Then, a toner is adhered to the latent image by magnetic brush developing methods and the like to develop it, and the toner image is transferred to transfer paper, followed by fixing to obtain a copied image.
However, the copied image obtained as described above is sometimes further copied as an original document. In such cases, when the copied image is supplied to an automatic document feeder of a copying machine, the surface of the copied image of the original document is rubbed with a paper feed roll of this device, thereby producing stains and blurs on the image.
In double-sided copying or multi-color copying, first copied image is fixed on a sheet, and then second copying is carried out on the sheet. At this time, the surface of the copied image is rubbed with a paper feed roll, thereby producing stains and blurs on the image. Further, when a plurality of sheets having copied images stored one over the other in a copying machine are taken out one by one with a paper feed roll, the back of one sheet having copied images and the copied image-bearing surface of another sheet are rubbed with each other, thereby producing stains and blurs on both the images, which results in a lowering of image quality.